Pseudo Wire Edge to Edge Emulation O. Nicklass
Internet-Draft RADVISION Ltd.
Intended status: Standards Track October 20, 2008
Expires: April 23, 2009
Managed Objects for TDM over Packet Switched Network (PSN)draft-ietf-pwe3-tdm-mib-11.txt
Status of this Memo
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This Internet-Draft will expire on April 23, 2009.
Abstract
This memo defines a portion of the Management Information Base (MIB)
for use with network management protocols in the Internet community.
In particular, it describes managed objects for pseudo wire
encapsulation for structured or unstructured TDM (T1, E1, T3, E3)
circuits over a Packet Switch Network (PSN).
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Figure 1
Comments should be made directly to PWE3 group at pwe3@ietf.org.
2. Conventions
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in RFC-2119 [BCP14].
3. Terminology
The Basic terminology used to refer to transmission direction in this
document is taken from [SATOP] draft that describes a mechanism for
transporting Structure-Agnostic (TDM) bit-streams over a packet-
oriented network. For simplifying this document the terminology is
used for structure and unstructured TDM as well.
"PSN-bound" references the traffic direction where TDM data is
received, adapted to packet based on number of payload bytes per
packet, assigned a relevant TDM header (Sequence numbers, flags, and
timestamps (if the RTP header is used)), prepended multiplexing layer
and PSN headers and sent into the PSN.
Conversely, The "CE-bound" references the traffic direction where
packets are received from the PSN, packet payloads are reassembled by
including a jitter buffer where payload of the received TDM packets
is stored prior to play-out to the TDM line. The size of this buffer
SHOULD be locally configurable to allow accommodation to the PSN-
specific packet delay variation.
The CE-bound TDM inter-working function (IWF) SHOULD use the sequence
number in the control word for detection of lost (LOPS) and mis-
ordered packets. If the RTP header is used, the RTP sequence numbers
MAY be used for the same purposes.
4. The Internet-Standard Management Framework
For a detailed overview of the documents that describe the current
Internet-Standard Management Framework, please refer to section 7 of
RFC 3410 [RFC3410].
Managed objects are accessed via a virtual information store, termed
the Management Information Base or MIB. MIB objects are generally
accessed through the Simple Network Management Protocol (SNMP).
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Objects in the MIB are defined using the mechanisms defined in the
Structure of Management Information (SMI). This memo specifies a MIB
module that is compliant to the SMIv2, which is described in STD 58,
RFC 2578 [RFC2578], STD 58, RFC 2579 [RFC2579] and STD 58, RFC 2580
[RFC2580].
5. Overview
This MIB module is designed to satisfy the following requirements and
constraints:
1. Fits within the architecture defined by [RFC3985] and [PWMIB].
2. The MIB module supports edge-to-edge emulation of any TDM
connections.
3. The MIB module configures the connection. The connection
specific behavior is provided via the supplement MIB modules.
4. The MIB module reports various alarms, counters and status
objects.
6. TDM MIB module usage6.1. Structure of TDM MIB
The MIB consists of five tables;
-The TDM PW Table (pwTDMTable) contains generic TDM information
regarding the PW connection. It contains the ifIndex of the TDM
interface, an index to an entry in the generic configuration table
(pwTDMCfgTable), an index to an entry in the specific configuration
table (pwCXXXCfgTable, where XXX can be TDMoIP or CESoPSN), config
error indications, and various status indications. The two indices
of the two configuration tables are providing the connection
parameters. The TDM interface can be a full link of any TDM type
like E1 or DS3 for example, or the interface of the bundle holding
the collection of time slots to be transmitted. Based on the TDM PW
type the relevant pwXXXCfgTable from the relevant MIB module will be
used. The specific types are:
o 17 Structure-agnostic E1 over Packet
o 18 Structure-agnostic T1 (DS1) over Packet
o 19 Structure-agnostic E3 over Packet
o 20 Structure-agnostic T3 (DS3) over Packet
o 21 CESoPSN basic mode (XXX=CESoPSN)
o 22 TDMoIP AAL1mode (XXX=TDMoIP)
o 23 CESoPSN TDM with CAS (XXX=CESoPSN)
o 24 TDMoIP AAL2 Mode (XXX=TDMoIP)
- The TDM generic parameter Table (pwTDMCfgTable, ) contains TDM
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generic configurable parameters for any TDM Type.
- The TDM Performance Current Table (pwTDMPerfCurrentTable) contains
TDM statistics for the current 15-minute period.
- The TDM Performance Interval Table (pwTDMPerfIntervalTable)
contains TDM statistics for historical intervals (usually 96 15-
minute entries to cover a 24 hour period).
- The TDM Performance one day Interval Table
(pwTDMPerf1DayIntervalTable) contains TDM statistics for historical
intervals accumulated per day. Usually 30 1-Day entries to cover a
monthly period.
6.2. TDM Connection configuration Procedure
Configuring a TDM PW involves the following steps:
First Configure the parameters of the interface specific layer using
DS1-MIB and or DS3-MIB.
Next, if applicable, create a bundle of Time Slots using DS0 Bundle
MIB [DS0MIB].
Next, create an entry in the pwTable and configure the PSN tunnels:
- Follow steps as defined in [PWMIB].
NOTE: The agent should create an entry in the pwTDMTable for any
entry created in the pwTable with pwType equal to a value between
(17) to (24).
Next complete the TDM PW configuration:
- If necessary, create an entry in the relevant pwXXXCfgTable and in
the pwTDMTable (suitable entries may already exist in both tables).
- Set the index of the relevant pwXXXCfgTable entry and of the
relevant pwTDMCfgTable entry in the pwTDMTable.
6.3. TDM PW Monitoring
Upon making the TDM PW operational, the pwTDMPerfCurrentTable,
pwTDMPerfIntervalTable, and PwTDMPerf1DayIntervalTable can be used to
monitor the various counters, indicators, and conditions of the PW.
All performance parameters are accumulated in daily intervals and in
fifteen minute intervals. The number of daily intervals kept by the
agent are based on the specific implementation. The fifteen minute
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intervals up to 96 intervals (24 hours worth) are all kept by the
agent. Fewer than 96 intervals of data will be available if the
agent has been restarted within the last 24 hours. Performance
parameters continue to be collected when the interface is down.
There is no requirement for an agent to ensure fixed relationship
between the start of a fifteen minute interval and any wall clock;
however some agents may align the fifteen minute intervals with
quarter hours. Performance parameters are of types PerfCurrentCount
and PerfIntervalCount. These textual conventions are all Gauge32,
and they are used because it is possible for these objects to
decrease.
7. Example of actual TDM PW Setup
This section provides an example of using the various MIB objects
described in the following section to set up a TDM PW connection.
First example, setting a connection of DS1 type. Second example
setting a connection with bandwidth of 3 DS0 (time slots).
While those examples are not meant to illustrate all options of the
MIB, they are intended as an aid to understanding some of the key
concepts. See [PWMIB] for an example of setting up PSN Tunnels.
First example:
1. Configure the DS1 interface using DS1-MIB.
2. If needed, Create an entry in the pwTDMCfgTable (assuming index =
10); Verify that there are no errors in the configuration using
the relevant object.
3. Get a new pwIndexNext [PWMIB] and create a new pwTable entry
using the value of pwIndexNext (assume here, the PW index = 20).
4. Set the pwType [PWMIB] of the new entry to the relevant value
(17) or (18). This should create a new entry in the pwTDMTable.
5. Configure the newly created TDM PW with the required pointers,
indices, the relevant entry in pwTDMCfgTable (index 10).
In [DS1MIB] dsx1IfIndex (ifIndex = 5)
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In pwTDMCfgTable entry: Set the connection characteristic
parameters:
{
pwTDMCfgPayloadSize = 43 -- payload bytes
pwTDMCfgPktReorder = FALSE
pwTDMCfgRtpHdrUsed = FALSE
pwTDMCfgJtrBfrDepth = 30000 -- micro-seconds
}
In pwTDMTable entry: Set the relevant ifIndex, the generic
TDM Index and the specific TDM index to complete creation:
{
pwTDMIfIndex = 5 -- IfIndex of associated entry
-- in DS1 table
pwGenTDMCfgIndex = 10 -- Index of associated entry
-- in pwTDMCfgTable.
pwRelTDMCfgIndex = 0 -- No Index in associated entry
-- in pwXXXCfgTable.
}
Verify that there are no error bits set in pwTDMConfigError.
Second example:
1. Configure the DS1 interface using DS1-MIB.
2. set up a bundle and get its dsx0BundleIfIndex. Setting up the
bundle should involve using IFMIB properly.
3. Since structured TDMoIP circuit is defined, the next MIB module
to be used is TDMoIP-MIB.
4. If needed, Create an entry in the pwTDMCfgTable (assuming index =
7):
5. If needed, Create an entry in the pwXXXCfgTable (index = 11).
XXX can be TDMoIP or CESoPSN
6. Verify that there are no error in the configuration using the
relevant object when signaling is in use.
7. Get a new pwIndexNext [PWMIB] and create a new pwTable entry
using the value of pwIndexNext.
8. Set the pwType [PWMIB] of the new entry to (24). This should
create a new entry in the pwTDMTable.
9. Configure the newly created TDM PW with the required pointers,
indices and the relevant entries in pwTDMCfgTable and in
pwXXXCfgTable (assuming indexes 7 and 11).
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pwTDMEntry OBJECT-TYPE
SYNTAX PwTDMEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"This table is indexed by the same index that was
created for the associated entry in the PW Table
(in the PW-STD-MIB).
- The PwIndex.
An entry is created in this table by the agent for every
entry in the pwTable with a pwType equal to one of the
following:
e1Satop(17), t1Satop(18), e3Satop(19), t3Satop(20),
basicCesPsn(21), basicTdmIp(22), tdmCasCesPsn(23),
tdmCasTdmIp(24).
Unless otherwise specified, all writeable objects in this
table MUST NOT be changed after row activation in the
generic pwTable (see [PWMIB])and values must persist
after reboot."
INDEX { pwIndex }
::= { pwTDMTable 1 }
PwTDMEntry ::= SEQUENCE {
pwTDMRate Integer32,
pwTDMIfIndex InterfaceIndexOrZero,
pwGenTDMCfgIndex PwCfgIndexOrzero,
pwRelTDMCfgIndex PwCfgIndexOrzero,
pwTDMConfigError BITS,
pwTDMTimeElapsed Integer32,
pwTDMValidIntervals Integer32,
pwTDMValidDayIntervals Integer32,
pwTDMLastEsTimeStamp TimeStamp
}
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pwTDMRate OBJECT-TYPE
SYNTAX Integer32
MAX-ACCESS read-write
STATUS current
DESCRIPTION
"The parameter represents the bit-rate of the TDM service
in multiples of the 'basic' 64 Kbit/s rate [TDMCP-EXT].
It complements the definition of pwType used in
PW-STD-MIB.
For structure-agnostic the following should be used:
a) Satop E1 - 32
b) Satop T1 emulation:
i) MUST be set to 24 in the basic emulation mode
ii) MUST be set to 25 for the 'Octet-aligned T1'
emulation mode
c) Satop E3 - 535
d) Satop T3 - 699
For all kinds of structure-aware emulation, this parameter
MUST be set to N where N is the number of DS0 channels
in the corresponding attachment circuit."
REFERENCE
"TDMCP-EXT"
DEFVAL { 32 }
::= { pwTDMEntry 1 }
pwTDMIfIndex OBJECT-TYPE
SYNTAX InterfaceIndexOrZero
MAX-ACCESS read-write
STATUS current
DESCRIPTION
"This is a unique index within the ifTable. It represents
the interface index of the full link or the interface
index for the bundle holding the group of
time slots to be transmitted via this PW connection.
A value of zero indicates an interface index that has yet
to be determined.
Once set, if the TDM ifIndex is (for some reason) later
removed, the agent SHOULD delete the associated PW rows
(e.g., this pwTDMTable entry). If the agent does not
delete the rows, the agent MUST set this object to
zero."
::= { pwTDMEntry 2 }
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pwGenTDMCfgIndex OBJECT-TYPE
SYNTAX PwCfgIndexOrzero
MAX-ACCESS read-write
STATUS current
DESCRIPTION
"Index to the generic parameters in the TDM configuration
table that appears in this MIB module. It is likely that
multiple TDM PWs of the same characteristic will share
a single TDM Cfg entry."
::= { pwTDMEntry 3 }
pwRelTDMCfgIndex OBJECT-TYPE
SYNTAX PwCfgIndexOrzero
MAX-ACCESS read-write
STATUS current
DESCRIPTION
"Index to the relevant TDM configuration table entry
that appears in one of the related MIB modules
such as TDMoIP or CESoPSN. It is likely that
multiple TDM PWs of the same characteristic will share
a single configuration entry of the relevant type.
The value 0 implies no entry in other related MIB"
::= { pwTDMEntry 4 }
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pwTDMConfigError OBJECT-TYPE
SYNTAX BITS {
notApplicable ( 0),
tdmTypeIncompatible ( 1),
peerRtpIncompatible ( 2),
peerPayloadSizeIncompatible ( 3)
}
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"Any of the bits are set if the local configuration is
not compatible with the peer configuration as available
from the various parameters options. Setting is done based
on signaling, or else value (0) will be set.
-tdmTypeIncompatible bit is set if the local configuration
is not carrying the same TDM type as the peer configuration.
-peerRtpIncompatible bit is set if the local configuration
is configured to send RTP packets for this PW, and the
remote is not capable of accepting RTP packets.
-peerPayloadSizeIncompatible bit is set if the local
configuration is not carrying the same Payload Size as the
peer configuration. "
::= { pwTDMEntry 5}
pwTDMTimeElapsed OBJECT-TYPE
SYNTAX Integer32 (1..900)
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of seconds, including partial seconds,
that have elapsed since the beginning of the current
measurement period. If, for some reason, such as an
adjustment in the system's time-of-day clock, the
current interval exceeds the maximum value, the
agent will return the maximum value."
::= { pwTDMEntry 6}
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pwTDMValidIntervals OBJECT-TYPE
SYNTAX Integer32 (0..96)
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of previous 15-minute intervals for which data
was collected.
An agent with TDM capability must be capable of supporting
at least n intervals. The minimum value of n is 4, The
default of n is 32 and the maximum value of n is 96.
The value will be n unless the measurement was (re-)
started within the last (n*15) minutes, in which case
the value will be the number of complete 15 minute
intervals for which the agent has at least some data.
In certain cases(e.g., in the case where the agent is
a proxy) it is possible that some intervals are unavailable.
In this case, this interval is the maximum interval number
for which data is available. "
::= { pwTDMEntry 7}
pwTDMValidDayIntervals OBJECT-TYPE
SYNTAX Integer32 (0..30)
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of previous days for which data
was collected.
An agent with TDM capability must be capable of supporting
at least n intervals. The minimum value of n is 1, The
default of n is 1 and the maximum value of n is 30."
::= { pwTDMEntry 8}
pwTDMLastEsTimeStamp OBJECT-TYPE
SYNTAX TimeStamp
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The value of sysUpTime at the most recent occasion at
which the TDM PW entered the ES or SES state."
::= { pwTDMEntry 11}
-- End of TDM PW table
-- PW Generic TDM PW Configuration Table
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pwTDMCfgIndexNext OBJECT-TYPE
SYNTAX Unsigned32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"This object contains the value to be used for
pwTDMCfgIndex when creating entries in the
pwTDMCfgTable. The value 0 indicates that no
unassigned entries are available. To obtain the
value of pwTDMCfgIndexNext for a new entry in the
pwTDMCfgTable, the manager issues a management
protocol retrieval operation. The agent will
determine through its local policy when this
index value will be made available for reuse."
::= { pwTDMObjects 2 }
pwTDMCfgTable OBJECT-TYPE
SYNTAX SEQUENCE OF PwTDMCfgEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"This table contains a set of parameters that may be
referenced by one or more TDM PWs in pwTDMTable."
::= { pwTDMObjects 3 }
pwTDMCfgEntry OBJECT-TYPE
SYNTAX PwTDMCfgEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"These parameters define the characteristics of a
TDM PW. They are grouped here to ease NMS burden.
Once an entry is created here it may be re-used
by many PWs.
Unless otherwise specified, all objects in this table
MUST NOT be changed after row activation (see [PWMIB])
if the row index is in use by an entry in pwTDMTable.
Rows must persist after reboot."
INDEX { pwTDMCfgIndex }
::= { pwTDMCfgTable 1 }
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pwTDMCfgRowStatus OBJECT-TYPE
SYNTAX RowStatus
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"Object used for creating, modifying, and deleting
a row from this table. The following objects cannot be
modified if the entry is in use and the status is active:
pwTDMCfgPayloadSize, pwTDMCfgRtpHdrUsed,
pwTDMCfgJtrBfrDepth, and pwTDMCfgPayloadSuppression.
The row cannot be deleted if the entry is in use"
::= { pwTDMCfgEntry 2 }
pwTDMCfgPayloadSize OBJECT-TYPE
SYNTAX Unsigned32
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The value of this object indicates the PayLoad Size (in bytes)
to be defined during the PW setUp. Upon TX, implementation
must be capable of carrying that amount of bytes.
Upon RX, when the LEN field is set to 0, the payload of
packet MUST assume this size, and if the actual
packet size is inconsistent with this length,
the packet MUST be considered to be malformed. "
::= { pwTDMCfgEntry 4 }
pwTDMCfgPktReorder OBJECT-TYPE
SYNTAX TruthValue
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"If set True: as CE bound packets are queued in the
jitter buffer, out of order packets are re-ordered. The
maximum sequence number differential (i.e., the range in
which re-sequencing can occur) is dependant on the depth
of the jitter buffer. See pwTDMCfgJtrBfrDepth.
NOTE: Some implementations may not support this feature.
The agent should then reject a SET request for true."
::= { pwTDMCfgEntry 5 }
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pwTDMCfgRtpHdrUsed OBJECT-TYPE
SYNTAX TruthValue
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"If set to False: an RTP header is not pre-pended to the
TDM packet."
REFERENCE
"SATOP"
DEFVAL { false }
::= { pwTDMCfgEntry 6 }
pwTDMCfgJtrBfrDepth OBJECT-TYPE
SYNTAX Unsigned32
UNITS "microsecond"
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The size of this buffer SHOULD be locally
configured to allow accommodation to the PSN-specific packet
delay variation.
If configured to a value not supported by the
implementation, the agent MUST return an error code
'jtrBfrDepth' in 'pwTDMConfigError '
NOTE: jitter buffers are a limited resource to
be managed. The actual size should be at least twice as big
as the value of pwTDMCfgJtrBfrDepth "
DEFVAL { 3000 }
::= { pwTDMCfgEntry 7 }
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pwTDMCfgSetUp2SynchTimeOut OBJECT-TYPE
SYNTAX Unsigned32
UNITS "millisecond"
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The amount of time the host should wait before declaring the
pseudo wire in down state, if the number of consecutive
TDM packets that have been received after changing the
adminstrative status to up and after finalization of
signaling (if supported) between the two PEs is smaller
than pwTDMCfgConsecPktsInSynch. Once the the pw has
OperStatus of 'up' this parameter is no longer valid. This
parameter is defined to ensure that the host does not
prematurely inform failure of the pw. In particular pw 'down'
notifications should not be sent before expiration of this
timer. This parameter is valid only after adminisrative
changes of the status of the pw. If the pw fails due to
network impairments a 'down' notification should be sent.
Object MAY be changed only when the related PW is
defined as not active."
DEFVAL {5000}
::= { pwTDMCfgEntry 11 }
pwTDMCfgPktReplacePolicy OBJECT-TYPE
SYNTAX INTEGER
{
allOnes (1),
implementationSpecific(2),
filler (3) --user defined
}
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"This parameter determines the value to be played when CE bound
packets have over/underflow the jitter buffer, or are missing
for any reason. This byte pattern is sent(played)on
the TDM line. Selecting implementationSpecific(2) implies
agent specific algorithm. Selecting filler(3) requires setting
of pwTDMCfgPktFiller.
Object MAY be changed only when the related PW is
defined as not active."
DEFVAL { allOnes } -- Play AIS
::= { pwTDMCfgEntry 12 }
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pwTDMCfgAvePktLossTimeWindow OBJECT-TYPE
SYNTAX Integer32
UNITS "millisecond"
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The length of time over which the average packet
loss rate should be computed to detect Excessive packet
loss rate.
Object MAY be changed only when the related PW is
defined as not active."
::= { pwTDMCfgEntry 13}
pwTDMCfgExcessivePktLossThreshold OBJECT-TYPE
SYNTAX Unsigned32
UNITS "Percent"
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"Excessive packet loss rate is detected by computing the
average packetloss rate over a pwTDMCfgAvePktLossTimeWindow
amount of time and comparing it with this threshold value.
The rate is expressed in precentage.
Object MAY be changed only when the related PW is
defined as not active."
::= { pwTDMCfgEntry 14 }
pwTDMCfgAlarmThreshold OBJECT-TYPE
SYNTAX Unsigned32
UNITS "milisec"
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"Alarms are only reported when the defect state persists
for the length of time specified by this object.
Object MAY be changed only when the related PW is
defined as not active."
DEFVAL { 2500 }
::= { pwTDMCfgEntry 15 }
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pwTDMCfgClearAlarmThreshold OBJECT-TYPE
SYNTAX Unsigned32
UNITS "milisec"
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"Alarm MUST be cleared after the corresponding defect is
undetected for the amount of time specified by this object.
Object MAY be changed only when the related PW is
defined as not active."
DEFVAL { 10000 }
::= { pwTDMCfgEntry 16 }
pwTDMCfgMissingPktsToSes OBJECT-TYPE
SYNTAX Unsigned32
UNITS "Percent"
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"Percent of missing packets detected (consecutive or not)
within a 1 second window to cause a Severely Error
Second (SES) to be counted.
Object MAY be changed only when the related PW is
defined as not active."
DEFVAL { 30 }
::= { pwTDMCfgEntry 17 }
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pwTDMCfgTimestampMode OBJECT-TYPE
SYNTAX INTEGER
{
notApplicable (1),
absolute (2),
differential (3)
}
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"Timestamp generation MAY be used in one of the following
modes:
1. Absolute mode: the PSN-bound IWF sets timestamps
using the clock recovered from the incoming TDM attachment
circuit. As a consequence, the timestamps are closely
correlated with the sequence numbers. All TDM implementations
that support usage of the RTP header MUST support this mode.
2. Differential mode: Both IWFs have access to a common high-
quality timing source, and this source is used for timestamp
generation. Support of this mode is OPTIONAL.
Object MAY be changed only when the related PW is
defined as not active."
::= { pwTDMCfgEntry 18 }
pwTDMCfgStorageType OBJECT-TYPE
SYNTAX StorageType
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"This variable indicates the storage type for this
row. Conceptual rows having the value permanent(4) must
allow write-access to all columnar objects."
::= { pwTDMCfgEntry 19 }
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pwTDMCfgPktFiller OBJECT-TYPE
SYNTAX Unsigned32 (0..255)
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"Filler byte pattern played out on the TDM
interface if pwTDMCfgPktReplacePolicy
was set to filler(3).
Object MAY be changed only when the related PW is
defined as not active."
DEFVAL
{ 255 } -- Play all ones, equal to AIS indications.
::= { pwTDMCfgEntry 20 }
pwTDMCfgName OBJECT-TYPE
SYNTAX SnmpAdminString
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"A descriptive string, prefereably unique name, to an entry
in this table.
Object MAY be changed at any time."
::= { pwTDMCfgEntry 21 }
-- End of Table
-- The following counters work together to integrate
-- errors and the lack of errors on the TDM PW. An error is
-- caused by a missing packet. Missing packet can be a result
-- of: packet loss in the network, (uncorrectable) packet out
-- of sequence, packet length error, jitter buffer overflow,
-- and jitter buffer underflow. The result is declaring whether
-- or not the TDM PW is in Loss of Packet (LOPS) state.
-- TDM PW Performance Current Table.
pwTDMPerfCurrentTable OBJECT-TYPE
SYNTAX SEQUENCE OF PwTDMPerfCurrentEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"The current 15 minute interval counts are in
this table.
This table provides per TDM PW performance information."
::= { pwTDMObjects 5 }
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pwTDMPerfCurrentUASs OBJECT-TYPE
SYNTAX PerfCurrentCount
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The counter associated with the number of
Unavailable Seconds encountered. Any consequtive
ten seconds of SES are counted as one UAS"
::= { pwTDMPerfCurrentEntry 8 }
pwTDMPerfCurrentFC OBJECT-TYPE
SYNTAX PerfCurrentCount
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"TDM Failure Counts (FC-TDM). The number of TDM failure
events. A failure event begins when the LOPS failure
is declared, and ends when the failure is cleared. A
failure event that begins in one period and ends in
another period is counted only in the period in which
it begins."
::= { pwTDMPerfCurrentEntry 9 }
-- End TDM PW Performance Current Interval Table
-- TDM PW Performance Interval Table.
pwTDMPerfIntervalTable OBJECT-TYPE
SYNTAX SEQUENCE OF PwTDMPerfIntervalEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"This table provides performance information per TDM PW
similar to the pwTDMPerfCurrentTable above. However,
these counts represent historical 15 minute intervals.
Typically, this table will have a maximum of 96 entries
for a 24 hour period, but is not limited to this. "
::= { pwTDMObjects 6 }
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pwTDMPerfIntervalEntry OBJECT-TYPE
SYNTAX PwTDMPerfIntervalEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"An entry in this table is created by the agent for
every pwTDMPerfCurrentEntry that is 15 minutes old.
The contents of the Current entry are copied to the new
entry here. The Current entry, then resets its counts
to zero for the next current 15 minute interval. "
INDEX { pwIndex, pwTDMPerfIntervalNumber }
::= { pwTDMPerfIntervalTable 1 }
PwTDMPerfIntervalEntry ::= SEQUENCE {
pwTDMPerfIntervalNumber Unsigned32,
pwTDMPerfIntervalValidData TruthValue,
pwTDMPerfIntervalDuration Unsigned32,
pwTDMPerfIntervalMissingPkts PerfIntervalCount,
pwTDMPerfIntervalPktsReOrder PerfIntervalCount,
pwTDMPerfIntervalJtrBfrUnderruns PerfIntervalCount,
pwTDMPerfIntervalMisOrderDropped PerfIntervalCount,
pwTDMPerfIntervalMalformedPkt PerfIntervalCount,
pwTDMPerfIntervalESs PerfIntervalCount,
pwTDMPerfIntervalSESs PerfIntervalCount,
pwTDMPerfIntervalUASs PerfIntervalCount,
pwTDMPerfIntervalFC PerfIntervalCount
}
pwTDMPerfIntervalNumber OBJECT-TYPE
SYNTAX Unsigned32 (1..96)
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"A number (normally between 1 and 96 to cover a 24 hour
period) which identifies the interval for which the set
of statistics is available. The interval identified by 1
is the most recently completed 15 minute interval, and
the interval identified by N is the interval immediately
preceding the one identified by N-1. The minimum range of
N is 1 through 4. The default range is 1 through 32. The
maximum value of N is 1 through 96."
::= { pwTDMPerfIntervalEntry 1 }
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pwTDMPerfIntervalUASs OBJECT-TYPE
SYNTAX PerfIntervalCount
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The counter associated with the number of
Unavailable Seconds encountered."
::= { pwTDMPerfIntervalEntry 11 }
pwTDMPerfIntervalFC OBJECT-TYPE
SYNTAX PerfIntervalCount
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"TDM Failure Counts (FC-TDM). The number of TDM failure
events. A failure event begins when the LOPS failure
is declared, and ends when the failure is cleared. A
failure event that begins in one period and ends in
another period is counted only in the period in which
it begins."
::= { pwTDMPerfIntervalEntry 12 }
-- End TDM PW Performance Interval Table
-- TDM PW 1day Performance Table
pwTDMPerf1DayIntervalTable OBJECT-TYPE
SYNTAX SEQUENCE OF PwTDMPerf1DayIntervalEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"This table provides performance information per TDM PW
similar to the pwTDMPerfIntervalTable above. However,
these counters represent historical 1 day intervals up to
one full month. The table consists of real time data, as
such it is not persistence across re-boot."
::= { pwTDMObjects 7 }
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DESCRIPTION
"The ability to set an index pointer
is not required."
OBJECT pwRelTDMCfgIndex
MIN-ACCESS read-only
DESCRIPTION
"The ability to set the an index pointer
is not required."
OBJECT pwTDMCfgPktReorder
MIN-ACCESS read-only
DESCRIPTION
"The ability to set the packet reordering
is not required.If the feature is not
supported, the value set by the agent MUST
be FALSE"
OBJECT pwTDMCfgRtpHdrUsed
MIN-ACCESS read-only
DESCRIPTION
"The ability to set whether to use the
RTP header or not is not required."
OBJECT pwTDMCfgPayloadSuppression
MIN-ACCESS read-only
DESCRIPTION
"The ability to set this object is not
required."
OBJECT pwTDMCfgPktReplacePolicy
MIN-ACCESS read-only
DESCRIPTION
"The ability to set the replace policy
is not required."
OBJECT pwTDMCfgStorageType
MIN-ACCESS read-only
DESCRIPTION
"The ability to set the storage type is
not required."
OBJECT pwTDMCfgPktFiller
MIN-ACCESS read-only
DESCRIPTION
"The ability to set the Filler pattern
is not required."
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pwTDMPerf1DayIntervalGroup OBJECT-GROUP
OBJECTS {
pwTDMPerf1DayIntervalValidData,
pwTDMPerf1DayIntervalDuration,
pwTDMPerf1DayIntervalMissingPkts,
pwTDMPerf1DayIntervalPktsReOrder,
pwTDMPerf1DayIntervalJtrBfrUnderruns,
pwTDMPerf1DayIntervalMisOrderDropped,
pwTDMPerf1DayIntervalMalformedPkt,
pwTDMPerf1DayIntervalESs,
pwTDMPerf1DayIntervalSESs,
pwTDMPerf1DayIntervalUASs,
pwTDMPerf1DayIntervalFC
}
STATUS current
DESCRIPTION
"Collection of Daily statistics objects for TDM PWs."
::= { pwTDMGroups 4 }
END
9. Security considerations
It is clear that this MIB module is potentially useful for monitoring
of TDM PWs. This MIB can also be used for configuration of certain
objects, and anything that can be configured can be incorrectly
configured, with potentially disastrous results.
There are a number of management objects defined in this MIB module
with a MAX-ACCESS clause of read-write and/or read-create. Such
objects may be considered sensitive or vulnerable in some network
environments. The support for SET operations in a non-secure
environment without proper protection can have a negative effect on
network operations. These are the tables and objects and their
sensitivity/vulnerability:
The pwTDMTable and pwTDMCfgTable contain objects of TDM PW parameters
on a Provider Edge (PE) device. Unauthorized access to objects in
these tables could result in disruption of traffic on the network.
The use of stronger mechanisms such as SNMPv3 security should be
considered where possible. Specifically, SNMPv3 VACM and USM MUST be
used with any SNMPV3 agent, which implements this MIB module.
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Administrators should consider whether read access to these objects
should be allowed, since read access may be undesirable under certain
circumstances.
Some of the readable objects in this MIB module (i.e., objects with a
MAX-ACCESS other than not-accessible) may be considered sensitive or
vulnerable in some network environments. It is thus important to
control even GET and/or NOTIFY access to these objects and possibly
to even encrypt the values of these objects when sending them over
the network via SNMP. These are the tables and objects and their
sensitivity/vulnerability:
The pwTDMTable, pwTDMPerfCurrentTable, pwTDMPerfIntervalTable and
pwTDMPerf1DayIntervalTable collectively show the TDM pseudo wire
connectivity topology and its performance characteristics.
If an Administrator does not want to reveal this information, then
these tables should be considered sensitive/vulnerable.
SNMP versions prior to SNMPv3 did not include adequate security.
Even if the network itself is secure (for example by using IPsec),
even then, there is no control as to who on the secure network is
allowed to access and GET/SET (read/change/create/delete) the objects
in this MIB module.
It is RECOMMENDED that implementers consider the security features as
provided by the SNMPv3 framework (see [RFC3410], section 8),
including full support for the SNMPv3 cryptographic mechanisms (for
authentication and privacy).
Further, deployment of SNMP versions prior to SNMPv3 is NOT
RECOMMENDED. Instead, it is RECOMMENDED to deploy SNMPv3 and to
enable cryptographic security. It is then a customer/operator
responsibility to ensure that the SNMP entity giving access to an
instance of this MIB module, is properly configured to give access to
the objects only to those principals (users) that have legitimate
rights to indeed GET or SET (change/create/delete) them.
10. IANA considerations
The MIB module in this document uses the following IANA-assigned
OBJECT IDENTIFIER values recorded in the SMI Numbers registry:
Descriptor OBJECT IDENTIFIER value
---------- -----------------------
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pwTDMMIB { mib-2 XXX }
Editor's Note (to be removed prior to publication): the IANA is
requested to assign a value for "XXX" under the mib-2 subtree and to
record the assignment in the SMI Numbers registry. When the
assignment has been made, the RFC Editor is asked to replace "XXX"
(here and in the MIB module) with the assigned value and to remove
this note.
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Full Copyright Statement
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